NETMOD T. Zhou
Internet-Draft S. Liu
Intended status: Standards Track Y. Xia
Expires: August 6, 2015 S. Jiang
Huawei Technologies Co., Ltd
February 2, 2015
YANG Data Models for Intent-based NEtwork MOdeldraft-zhou-netmod-intent-nemo-00
Abstract
This document describes a basic YANG data model for network intent.
The basic model can be augmented by additional YANG modules defining
data models for intent related protocols and functions to support
various network scenarios and applications. The basic network intent
data model provides common building blocks for extensions, such as
specific node and policy information.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on August 6, 2015.
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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Internet-Draft YANG Model for Intent-based NEtwork MOdel February 2015
abstraction for network services while concealing various
implementation techniques and multi-vendor devices.
This document introduces YANG [RFC6020] [RFC6021] data models for
network intent based on NEMO abstraction. This set of models
facilitates the standardization for the interface of intent
networking. The basic model can be augmented by additional YANG
modules defining data models for intent related protocols and
functions to support various different network scenarios and
applications. The basic network intent data model provides common
building blocks for extensions, such as specific node and policy
information.
2. Requirements Language and Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
[RFC2119] when they appear in ALL CAPS. When these words are not in
ALL CAPS (such as "should" or "Should"), they have their usual
English meanings, and are not to be interpreted as [RFC2119] key
words.
Intent-based NEtwork MOdel provides a high level description of
requirements to network with the abstraction from top down. It
conceals complexity to the network implementation but eases the
application invocation.
3. NEMO YANG Model Overview
The 80/20 rule of thumb in network application is that 80% of network
applications only use 20% of the network capability. Most of the
network operation is the combination of 4 basic operations: node,
link, flow and policy, of which the network intent comprises as shown
in Figure 1.
+---------------------------------------------+
| network intent |
| |
| +------+ +-----+ +------+ +--------+ |
| | node | |link | | flow | | policy | |
| +------+ +-----+ +------+ +--------+ |
+---------------------------------------------+
Figure 1
o Node operation includes creation, modification and deletion of a
network element (NE).
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Internet-Draft YANG Model for Intent-based NEtwork MOdel February 2015
leaf type{
type link-type;
mandatory true;
description "Specifies the concrete type of the link entity
object, there are different properties defination
for different type link";
}
container endnodes{
leaf one-node-id{
type yang:uuid;
mandatory true;
description "Uniquely identifies node entity object which
is as the endpoint of the link.";
}
leaf another-node-id{
type yang:uuid;
mandatory true;
description "Uniquely identifies node entity object which
is as the endpoint of the link.";
}
}
container properties{
}
}
}
3.3. Flow Intent Module3.3.1. Design of flow intent module
The flow intent model describes a sequence of packets with certain
common characters, such as source/destination IP address, port, and
protocol. From the intent perspective, flow is the special traffic
with user concern, which may be per device or across many devices.
So the flow characters also include ingress/egress node, and so on.
The following figure shows the model abstraction.
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Internet-Draft YANG Model for Intent-based NEtwork MOdel February 20154. Security Considerations
The YANG module defined in this memo is designed to be accessed via
the NETCONF protocol [RFC6241]. The lowest NETCONF layer is the
secure transport layer and the mandatory-to-implement secure
transport is SSH [RFC6242]. The NETCONF access control model
[RFC6536] provides the means to restrict access for particular
NETCONF users to a pre-configured subset of all available NETCONF
protocol operations and content.
There are a number of data nodes defined in the YANG module which are
writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., <edit-config>)
to these data nodes without proper protection can have a negative
effect on network operations.
5. IANA Considerations
This memo includes no request to IANA.
6. Acknowledgements
The authors would like to thanks the valuable comments made by Wei
Cao, Xiaofei Xu, Fuyou Miao and Wenyang Lei.
This document was produced using the xml2rfc tool [RFC2629].
7. Informative References
[I-D.xia-sdnrg-nemo-language]
Xia, Y., Jiang, S., Zhou, T., and S. Hares, "NEMO (NEtwork
MOdeling) Language", draft-xia-sdnrg-nemo-language-01
(work in progress), October 2014.
[I-D.xia-sdnrg-service-description-language]
Xia, Y., Jiang, S., and S. Hares, "Requirements for a
Service Description Language and Design Considerations",
draft-xia-sdnrg-service-description-language-01 (work in
progress), October 2014.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629,
June 1999.
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